Seasonal Swings: Managing Tire Air Pressure Year-Round

Picture this: it's a scorching summer afternoon, around 5 PM, and you're ready to call it a day. You walk to your car, settle into the driver's seat, and start the engine, eager to cool off with the AC. But wait, the dashboard is blinking: your tire pressure is too high. Reluctantly, you step out of the car to release some air. These tire pressure fluctuations, a common occurrence throughout the year, can be a real hassle. But have you ever wondered what causes these changes as the seasons shift?

A couple hundred years ago, some really smart chemist named Joseph Louis Gay-Lussac made a significant discovery about gases. He found that when a fixed amount of gas is heated in a container with a constant volume, the pressure of the gas increases proportionally to the increase in temperature. In simpler terms, as the temperature of a gas rises, so does its pressure. This principle, now known as Gay-Lussac's Law, is a cornerstone of gas chemistry and is the key to understanding why tire pressure changes with the seasons.

By applying Gay-Lussac's Law, we can explain why tire pressure fluctuates throughout the year. In the summer, the scorching heat will raise the temperature of the air particles inside your car tires up, driving the tire pressure up with it. Conversely, the cold months of winter will cool down the air particles inside your tires, resulting in a tire pressure drop. Likewise, it is essential for car owners to frequently check and adjust tire pressure throughout the year as necessary according to the manufacturer's recommendations, which can most often be found on the inside of the driver's door. 

Quick Tip: When adding or taking out air from your car tires, it is essential to do so when the car is cold (before driving). This is because, while driving, the friction between the tires and the ground converts the kinetic energy of the wheels into thermal energy, heating the tires and consequently artificially inflating their air pressure. Adjusting your tire air pressure before you drive will ensure that it is calibrated to the environmental temperature.